A boy. I don't know why, I've just always seen myself having a son one day. Possibly more children, but always at least one son. I think the bond I have with my father is something really special and something unique to father-son relationships, I'd like that bond with my own child.
I think it's 'cause I'm already a boy and know what it's like to grow up as a boy. Having a girl seems like it would be more interesting and new to me. Though I am aware having a child is the same as being a child lol. Was just my initial feeling anyway.